NIF 2.0 AKSW (SoC) - Refactoring / Format update

- Separation of concerns in NIF 2.0:
  * Spotlight should to provide only the data. Now It (re)uses an external library that knows all details about NIF format.

- Main and Rest poms:
  * Removing unused library: any23;
   
- OntologyType.scala:
  * It is not correct concatenate DBpedia ontology prefix when a type is a vocabulary specification (e.g foaf:Person)
  * For a small string, it is enough (and memory-oriented) to use .concat method instead of create a StringBuilder